6. On the board, set ‘BOOT0‘ to 1 (will boot from system memory which contains an UART to flash uploader). Press RESET button.
7. In the Arduino IDE, choose ‘Upload‘. On the board, the blue LED will start to flash.
8. After upload completed, your sketch will start. If you want your uploaded sketch to boot automatically after next power-on/reset, set ‘BOOT0‘ back to 0 (will boot from program memory). Press RESET button.